Datasheet

PIC16(L)F1938/9
DS40001574C-page 374  2011-2013 Microchip Technology Inc.
RETFIE Return from Interrupt
Syntax: [ label ] RETFIE
Operands: None
Operation: TOS
 PC,
1  GIE
Status Affected: None
Description: Return from Interrupt. Stack is POPed
and Top-of-Stack (TOS) is loaded in
the PC. Interrupts are enabled by
setting Global
Interrupt Enable bit, GIE
(INTCON<7>). This is a 2-cycle
instruction.
Words: 1
Cycles: 2
Example:
RETFIE
After Interrupt
PC = TOS
GIE =
1
RETLW Return with literal in W
Syntax: [ label ] RETLW k
Operands: 0
 k  255
Operation: k
 (W);
TOS
 PC
Status Affected: None
Description: The W register is loaded with the 8-bit
literal ‘k’. The program counter is
loaded from the top of the stack (the
return address). This is a 2-cycle
instruction.
Words: 1
Cycles: 2
Example:
TABLE
CALL TABLE;W contains table
;offset value
• ;W now has table value
•
•
ADDWF PC ;W = offset
RETLW k1 ;Begin table
RETLW k2 ;
•
•
•
RETLW kn ; End of table
Before Instruction
W = 0x07
After Instruction
W = value of k8
RETURN Return from Subroutine
Syntax: [ label ] RETURN
Operands: None
Operation: TOS
 PC
Status Affected: None
Description: Return from subroutine. The stack is
POPed and the top of the stack (TOS)
is loaded into the program counter.
This is a 2-cycle instruction.
RLF Rotate Left f through Carry
Syntax: [ label ] RLF f,d
Operands: 0
 f  127
d
 [0,1]
Operation: See description below
Status Affected: C
Description: The contents of register ‘f’ are rotated
one bit to the left through the Carry
flag. If ‘d’ is ‘
0’, the result is placed in
the W register. If ‘d’ is ‘
1’, the result is
stored back in register ‘f’.
Words: 1
Cycles: 1
Example:
RLF REG1,0
Before Instruction
REG1 = 1110 0110
C=0
After Instruction
REG1 = 1110 0110
W = 1100 1100
C=1
Register fC